Elapsed Revolutions (Front)

The Elapsed Revolutions (Front) label reports the number of revolutions that the front wheel of a four-wheel drive vehicle has turned at the current time point of the simulation. This figure is reported because the front and rear drive wheels of a four-wheel-drive vehicle often turn at different rates due to skidding of the front wheel.

When a four-wheel drive vehicle is simulated, the revolutions of both the rear drive wheel and the front drive wheel must be tracked separately. This is because the front wheel usually has less traction than the rear wheel, due to weight transfer from the front of the vehicle to the rear of the vehicle as the car accelerates. Reduced traction often leads to skidding of the front wheel, which causes it to turn more than the rear wheel.

When this happens, the front wheel depletes its revolutions faster than the rear wheel, causing the car to stop, even though the rear wheel still has some revolutions left. This is why the simulation stops before all of the projected revolutions for both wheels have taken place.